Isotropic Three-Dimensional Molecular Conductor Based on the Coronene Radical Cation

Yukihiro Yoshida, Mitsuhiko Maesato, Yoshihide Kumagai, Motohiro Mizuno, Kazuhide Isomura, Hideo Kishida, Masanari Izumi, Yoshihiro Kubozono, Akihiro Otsuka, Hideki Yamochi, Gunzi Saito, Kaplan Kirakci, Stéphane Cordier, Christiane Perrin

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

In this study, we obtained the first cation radical solid of a highly symmetric (D6h) polyaromatic hydrocarbon, coronene, by electrooxidation. The (coronene)3Mo6Cl14 salt, which is formed with an Oh-symmetric molybdenum cluster unit Mo6Cl142-, has an isotropic cubic structure with Pm3¯m symmetry. The presence of two orientations for the coronene molecules related by an in-plane 90° rotation (merohedral disorder) allows for fourfold symmetry along the <100> direction. The disorder has dynamic features because 2H NMR spectroscopic studies revealed that the coronene molecules undergo an in-plane flipping motion. The observation of two motional sites with significantly different rotational rates (300 Hz and 5 MHz at 103 K) in an approximate 2:1 ratio appears to be consistent with the splitting of a Raman-active A1g mode, confirming a random charge-disproportionated state instead of a uniform partially-charged state. The slower- and faster-rotating species are assigned to charge-rich and charge-poor coronenes, respectively, with respect to C-H···Cl hydrogen bonds with neighboring Mo6Cl142- cluster units. The electrical conductivity of the salt is rather high but is well-described by a three-dimensional (3D) variable-range hopping mechanism, which is possibly associated with the random charge disproportionation. These results provide a significant step forward in developing an isotropic 3D π-conducting system composed of planar π-conjugated molecules.

Original languageEnglish
Pages (from-to)3871-3878
Number of pages8
JournalEuropean Journal of Inorganic Chemistry
Volume2014
Issue number24
DOIs
Publication statusPublished - Aug 1 2014

Keywords

  • Charge transfer
  • Cluster compounds
  • Conducting materials
  • Magnetic properties
  • Solid-state structures

ASJC Scopus subject areas

  • Inorganic Chemistry

Fingerprint Dive into the research topics of 'Isotropic Three-Dimensional Molecular Conductor Based on the Coronene Radical Cation'. Together they form a unique fingerprint.

  • Cite this

    Yoshida, Y., Maesato, M., Kumagai, Y., Mizuno, M., Isomura, K., Kishida, H., Izumi, M., Kubozono, Y., Otsuka, A., Yamochi, H., Saito, G., Kirakci, K., Cordier, S., & Perrin, C. (2014). Isotropic Three-Dimensional Molecular Conductor Based on the Coronene Radical Cation. European Journal of Inorganic Chemistry, 2014(24), 3871-3878. https://doi.org/10.1002/ejic.201400119